See I'm thinking it's already the other way around... Kang has already been everywhere in the MCU and they planned for this with The Avengers. When Fury brings up his line about the "pharaohs of old" and things being buried I think it'll thematically tie into some of these secrets and why the Ant and boot lines are so important.

He was aleady Rama Tut, long before his influence on the timeline was buried like the pharaoh he once was, but he diverged that timeline, gave up power and the result is the Immortus we see in Marvel's movies. Has become a lot wiser. He's sort of like the beyonder or the being that set up Korvac, grandfather time, and the being that set up Magus as characters involved with time travel or time paradoxes. The kicker would be he's been working against Thanos this whole time, making slight adjustments to the timeline and acting sort of in unison with the beyonder.

One version of Kang masquerading as the being from before time Cthon created the alternate version of the skrulls and gave them their Egyptian look.... put them in Thanos's charge. Immortus is playing a very dangerous game against Thanos until the very end because this isn't Kang, it's Immortus who watches over millions of years of progression and tries to preserve timelines once he learns to stop messing with them too much.